By Sharon Terlep

A nearly 400-year-old fight over water rights is coming to a head along the banks of the Potomac River -- and pulling consumer products giant Procter & Gamble Co. into the fray.

West Virginia is threatening to sue Maryland if the state refuses to grant the mountain state unfettered access to water in the Potomac River, a portion of which defines the border between the two states.

West Virginia needs the water to support a $500 million manufacturing plant that P&G plans to build on its side of the Potomac, roughly 25 miles fromhistoric Harpers Ferry. P&G bought the 450-acre site in 2014 and has started construction on a facility that will start making Pantene shampoos and Old Spice body wash in 2018.

In a Nov. 2 letter to Maryland officials, West Virginia Attorney General Patrick Morrisey said the water treatment facility that will supply water to the P&G factory "has an urgent need" to increase capacity beyond limits imposed by Maryland.

He argues that Maryland's control over the Potomac River water is limited by an 1785 compact negotiated by George Washington, four years before becoming the first U.S. president, as well as a 2003 U.S. Supreme Court decision. Disputes over the river date back to the 1600s when Virginia and Maryland were both British colonies and West Virginia wasn't yet its own territory.

The office of Maryland Attorney General Brian Frosh said this week it is preparing a response and declined further comment.

The move alarmedlocals, who are counting on the factory to bring 700 jobs to the region, and sent P&G scrambling to contain the fallout.

On Tuesday, P&G said it has recently been reassured by officials in the county where the plant will be located that there will be adequate water for the factory and construction on the plant remains on track. Doug Copenhaver, president of the Berkeley County Commission, on Tuesday said the county has enough water to meet P&G's needs even if the state fails to win rights to draw more water from the Potomac.

The county water treatment plant is authorized to draw four million gallons a day from the Potomac. It currently draws 2.4 million and the P&G plant will require an additional 1.3 million, he said. The plant can also use other water sources within the region. "We have plenty of water, " Mr. Copenhaver said.

A spokesman for West Virginia Attorney General said the P&G factory will result in additional residential and industrial development that will push the county over the four million gallons a day it currently draws from the river.

The flare up, in a sleepy but fast-growing part of West Virginia famous for white-water rafting and Civil War history, is the type of skirmish increasingly common in Western states as rural and urban interests squabble over a resource diminished by drought and strained by a growing population. Water isn't so scarce in the mid-Atlantic, but growth in West Virginia combined with sprawl from Virginia and Maryland suburbs of Washington, D.C., has made water access more of an issue.

Maryland officially began regulating access to the Potomac in 1933 when it implemented a permit process for entities outside the state wishing to draw from the Potomac, said Adam Van Grack, a Maryland attorney who has litigated numerous disputes involving access to the region's rivers. The state approved all requests until the 1990swhen it started to turn some down amid rapid development in surrounding areas, he said.

Ever since the 2003 Supreme Court ruling which granted Virginia access to the river, "West Virginia has been waiting for a time to raise this issue," Mr. Van Grack said. "This plant is the straw that broke the camel's back, and now they are asserting their muscle over rights to the Potomac River."

Write to Sharon Terlep at sharon.terlep@wsj.com

(END) Dow Jones Newswires

November 23, 2016 05:44 ET (10:44 GMT)

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